Chlorpyrifos

The toxic pesticide now harming our children and environment

For half a century, U.S. staple foods such as corn, wheat, apples and citrus have been sprayed with chlorpyrifos, a dangerous pesticide that can damage the developing brains of children, causing reduced IQ, loss of working memory, and attention deficit disorders.

Earthjustice, among other groups, has for years pushed the U.S. Environmental Protection Agency to ban chlorpyrifos, as it is known to harm health, water and wildlife. The EPA was expected to make a decision by March 31, under a court order deadline. On March 29, the EPA refused to ban the pesticide. (Read reactions to the EPA's decision.)

“EPA is refusing to ban a pesticide that harms children’s brains. It is acting contrary to the law, the science, and a court order. In a word: unconscionable,” said Patti Goldman, managing attorney at Earthjustice, in response to the EPA's decision. A week after the EPA's announcement, Earthjustice, representing Pesticide Action Network and the Natural Resources Defense Council, asked the U.S. Court of Appeals for the Ninth Circuit to order the EPA to act based on its own scientific conclusions and permanently ban chlorpyrifos.

Here’s what you should know about chlorpyrifos and the ongoing struggle to keep this dangerous chemical away from our food, water, and wildlife:

TP Martins / CC BY-NC-SA 2.0

Since the 1960s, staple foods in the United States have been sprayed with chlorpyrifos, a dangerous pesticide that can permanently damage the developing brain of children and poison farmworkers.

What is chlorpyrifos?

Chlorpyrifos (pronounced: klawr-pir-uh-fos) is a neurotoxic pesticide widely used in U.S. agriculture. Generally sprayed on crops, it’s used to kill a variety of agricultural pests. It has a slightly skunky odor, similar to rotten eggs or garlic, and can be harmful if it is touched, inhaled, or eaten.

Chlorpyrifos is acutely toxic and associated with neurodevelopmental harms in children. Prenatal exposures to chlorpyrifos are associated with lower birth weight, reduced IQ, loss of working memory, attention disorders, and delayed motor development.

Acute poisoning suppresses the enzyme that regulates nerve impulses in the body and can cause convulsions, respiratory paralysis, and, in extreme cases, death. Chlorpyrifos is one of the pesticides most often linked to pesticide poisonings.

How are people exposed to chlorpyrifos?

People are exposed to chlorpyrifos through residues on food, drinking water contamination, and toxic spray drift from pesticide applications. Farmworkers are exposed to it from mixing, handling, and applying the pesticide; as well as from entering fields where chlorpyrifos was recently sprayed. Residential uses of chlorpyrifos ended in 2000 after EPA found unacceptable risks to kids.

Children often experience greater exposure to chlorpyrifos and other pesticides because they frequently put their hands in their mouths and, relative to adults, they eat more fruits and vegetables, and drink more water and juice for their weight.

Annette Dubois / CC BY 2.0

Children often experience greater exposure to chlorpyrifos because they drink more water and juice for their weight, relative to adults, and frequently put their hands in their mouths.

Lance Cheung / USDA

A farmworker gathers sweet potatoes in Mechanicsville, VA. Sweet potatoes are one of the many crops that chlorpyrifos is used on. Agricultural workers are at high risk for pesticide poisoning.

Chris Jordan-Bloch / Earthjustice

Jim Cochran, a strawberry farmer, was poisoned by pesticides. People told him no one cared about healthy food and healthy workers. He decided to prove them wrong. More on Jim's story

Why do we need a ban?

A growing body of evidence shows that prenatal exposure to very low levels of chlorpyrifos—levels far lower than what EPA was previously using to establish safety standards—harms babies permanently. Peer-reviewed studies that have tracked real-world exposures of mothers and their children to chlorpyrifos have associated the pesticide with similar findings.

Chlorpyrifos is found at unsafe levels in the air at schools, homes, and communities in agricultural areas.

All workers who mix and apply chlorpyrifos are exposed to unsafe levels of the pesticide even with maximum personal protective equipment and engineering controls.

Field workers are allowed to re-enter fields within 1–5 days after pesticide spraying, but unsafe exposures continue on average 18 days after applications.

Farmworkers and people living in agricultural communities, particularly children, are disproportionately affected by this toxic pesticide. In addition to food exposures, they are more likely to have contaminated drinking water, and they are, quite literally, getting hit from all sides by drift exposures at school, daycare, on the playground, at work, and in their homes.

Chris Jordan-Bloch / Earthjustice

Farmworkers harvest strawberries in Salinas, CA. Farmworkers and people living in agricultural communities are disproportionately affected by this toxic pesticide.

Lance Cheung / USDA

More than half of all apples in the U.S. are sprayed with chlorpyrifos, a pesticide considered too toxic for residential use. Yet, the substance can still be used on our food.

Which crops have chlorpyrifos on them?

Chlorpyrifos is used on a wide variety of crops including apples, oranges, strawberries, corn, wheat, citrus and other foods families and their children eat daily.

In fact, over half of all apples and broccoli in the U.S. are sprayed with chlorpyrifos. USDA’s Pesticide Data Program found chlorpyrifos residue on citrus and melons even after being washed and peeled. By volume, chlorpyrifos is most used on corn and soybeans, with over a million pounds applied annually to each crop.

Lance Cheung / USDA

A corn field in Wharton County, TX. More than a million pounds of chlorpyrifos are applied to corn crops each year.

Tarnie / CC BY-NC-ND 2.0

Strawberries are one of the many crops that chlorpyrifos is used on. The 1996 Food Quality Protect Act requires EPA to ensure with reasonable certainty that “no harm will result to infants and children from aggregate exposure” to pesticides.

What does the law require?

Following the release of a pivotal 1993 report by the National Academy of Sciences, Congress strengthened protections for children from pesticides. The NAS report criticized EPA for treating children like “little adults” by failing to address the unique susceptibility of children to pesticide exposures based on the foods they eat, their play, and sensitive stages of development.

The 1996 Food Quality Protect Act—passed unanimously in Congress—requires EPA to protect children from unsafe exposures to pesticides. The FQPA requires EPA to ensure with reasonable certainty that “no harm will result to infants and children from aggregate exposure” to pesticides. EPA cannot take industry costs into consideration when protecting children from harmful pesticides, because FQPA is a health-based standard.

If EPA cannot ensure that a pesticide won’t harm children, the law requires EPA to ban uses of the pesticide.

Nicolas Michaud / CC BY-NC-ND 2.0

Children exposed in utero are particularly at risk. Pesticide drift reaches unsafe levels at 300 feet from the field’s edge.

What are the current legal issues?

Seven years later, following several lawsuits and delays, EPA had still not acted on the petition. In September 2014, on behalf of PAN and NRDC, Earthjustice filed a petition in the 9th Circuit Court of Appeals to compel EPA to act on the petition.

The following year, while calling EPA delays “egregious” and noting the agency sent a “litany of partial status reports, missed deadlines, and vague promises of future action,” the court ordered EPA to issue a final response to the petition by October 31, 2015.

That deadline was not met, and last August the court said EPA had to take final action on the petition by March 31 of this year. EPA’s own human health risk assessments show that there are no safe uses for chlorpyrifos.

Previous updates: On March 29, 2017, despite the overwhelming evidence that the pesticide harms children, workers and the environment, the EPA issued a decision refusing to ban the pesticide, because the agency wanted to continue studying the science.

On April 5, following EPA's refusal to ban chlorpyrifos, Earthjustice—representing Pesticide Action Network and the Natural Resources Defense Council—asked the court to order the EPA to act based on the agency's own scientific conclusions, which, under the law, would require EPA to ban chlorpyrifos. EPA opposed the motion on April 28, and Earthjustice filed a reply on May 3. The groups are asking the U.S. Court of Appeals for the Ninth Circuit to direct the EPA to make a decision on the merits of the petition within 30 days. Specifically, the groups are asking the court to order EPA to ban all food uses of chlorpyrifos based on its findings that the pesticide is unsafe. On July 18, the Ninth Circuit Court of Appeals declined to direct the EPA to decide on whether to ban chlorpyrifos.

On June 6, 2017, Earthjustice filed an administrative appeal to the EPA, on behalf of a dozen health, labor and civil rights organizations, urging the federal government to ban chlorpyrifos. The new appeal challenges, on its merits, the EPA’s March action that allows chlorpyrifos to continue to be used on food crops. The attorneys general of New York, California, Washington, Massachusetts, Maine, Maryland and Vermont filed their own appeal that same day, also calling for a ban. It is now up to EPA Administrator Scott Pruitt to decide the appeal.

On Dec. 20, 2018, the court granted a motion to expedite the case and denied EPA’s motion to dismiss Earthjustice’s petition to review the Pruitt order on chlorpyrifos. Several states who have also called for a chlorpyrifos ban were granted permission to intervene in the case.

Is there anything I can do?

Urge your elected officials to keep this toxic pesticide out of our food, our water, our schools and yards, and our bodies.

Since the EPA's refusal on March 29 to ban chlorpyrifos, 47,114 Earthjustice supporters have sent messages to their Congressional representatives, governor and state Attorney General, asking them to hold the EPA accountable. Read just a few of the messages—and send your own message today.

An apple a day won't keep the doctor away if it has pesticides in it.

– Eveline,Ellicott City, MD

As an RN who worked in the ER in a farming community AND as the mother of a childhood cancer survivor who had a neurological tumor the size of a baseball in her tiny chest at age 8, I am horrified this neurotoxin is not banned! I will speak, write, or show up in any way to protect our food, our water, our children!

– Cheryl,Lake Oswego, OR

I have personally witnessed some of the effects of this toxin and it is outrageous that after it being banned for residential use 17 years ago, that it can continue to expose young children and their parents to its effects in the fields where most of our fruits and vegetables are harvested. Please change this decision now.

– Robert,Sherman, TX

As a former toxicological pathologist, I know that when a well-run study shows these kinds of results, only a fool would dismiss the data and the conclusions. Pruitt's refusal to follow through on banning chlorpyrifos amounts to intentional poisoning of the population and the environment.

He is dismissing evidence that chlorpyrifos toxicity impacts bystanders (not someone who handles or applies the chemical)—i.e. data from children (rather than a controlled rat study).

– Laurie,Friday Harbor, WA

As a neuroscientist, I am well aware of the dangers pesticides like chlorpyrifos pose to normal brain function.

The effects on adult brains are striking, but the effects on children's developing brains are even more serious. We do not know how to reverse the adverse effects of pesticide exposure on brain development. The effects of abnormal brain development are life-long.

The benefits of chlorpyrifos use do not come close to outweighing the heavy costs to the health and brain function of those who are exposed.

– Cheryl,Stanton, NJ

I have family members who have/have died from various diseases on the rise linked to pesticides and toxins including Parkinson's which took my dad's life several months ago. It's imperative that we keep our food supply safe and keep our health a priority.

– Sergio,Los Angeles, CA

This has been a long-standing issue that I have worked on for many years (30?). Having relatives and friends that live in the Central Valley and work there, they are severely affected by this chemical with respiratory issues especially asthma—adults & children. Thank you for your time and consideration and look forward to hearing positive news from you soon.

– John,Pasadena, CA

As a cancer survivor, I am increasingly alarmed at the number and amount of chemicals we are bombarded with ... we allow commercial enterprises to poison all of us. Please reconsider.

– Sara,Elkhorn, WI

A Timeline of Chlorpyrifos

World War II-era

The Nazis developed organophosphates during World War II as nerve gas agents. (Sarin gas is in this family of chemicals.) After the war, the chemical companies adapted the organophosphates to be used as pesticides, primarily as insecticides.

1965

Chlorpyrifos is an organophosphate pesticide first registered as an insecticide in the U.S. for both agricultural and residential uses, before Silent Spring and adoption of environmental and health standards in U.S. laws governing pesticide use.

1995

EPA orders DowElanco to pay $876,000, the largest fine up to that time, for violating a federal law requiring it to report human health problems from chlorpyrifos.

2000

Dow stops home uses of chlorpyrifos after EPA finds unacceptable risks to children who crawl on treated carpets or hug their pets after a flea bomb. Termiticide uses are also phased out.

2001 & 2006

EPA re-registers chlorpyrifos and the other organophosphates, purporting to bring them into compliance with health and environmental standards put in place after they were initially registered for use in the United States. EPA allowed risks of poisonings to workers to continue, ignored pesticide drift, and dismissed the growing evidence that prenatal exposures damage children’s brains.

2000s

Air monitoring detects chlorpyrifos at levels that exceed what EPA considered safe for children. California Air Resources Board monitoring finds chlorpyrifos at elementary schools and other sites near orange fields in Tulare County, California, at unsafe levels.

2007

On behalf of United Farm Workers and other farmworker advocates, Earthjustice and Farmworker Justice file a lawsuit challenging EPA’s re-registration of chlorpyrifos despite the harm to workers and from toxic drift.

Pesticide Action Network and Natural Resources Defense Council file petition seeking a ban on chlorpyrifos based on evidence of brain damage from prenatal exposures and toxic drift.

Centers for Children’s Environmental Health and Disease Prevention Research at Columbia, Berkeley, and Mt. Sinai study children exposed to CPR in utero and find statistically significant neurodevelopmental harm including reduced IQ, delayed development, loss of working memory, and attention deficit disorders. A 2012 study found chlorpyrifos exposure led to changes in the physical structure of the developing brain.

2011

EPA documents toxic drift from chlorpyrifos in its preliminary risk assessment, and EPA acknowledges its legal obligation to protect children from pesticide drift.

2012

EPA reaches an agreement with the chlorpyrifos registrants to put buffer zones around schools, day cares, homes, playfields, and other places occupied by people. The buffer zones vary in size from 10 feet for groundboom applications, 10–50 for airblast applications depending on the amount applied, and 10–100 for aerial spraying depending on the amount applied and the droplet size. In setting the buffer zones, EPA ignored direct drift onto people and inhalation exposures from groundboom and airblast spraying.

(1) acknowledging the extensive body of peer-reviewed science correlating chlorpyrifos exposure with brain damage to children and that the brain damage occurred at exposures far below EPA’s regulatory endpoint based on acute pesticide poisoning risks;

(2) finding acute poisoning risks of concern to workers from over 200 activities, including mixing and loading various pesticide formulations, airblast, aerial, and groundboom spraying, and re-entering fields after spraying to perform tasks like thinning, irrigating, and hand harvesting.

March–June, 2015

EPA represented that it was going to negotiate with the registrants to agree to mitigation or stopping activities that expose workers to excessive poisoning risks. By June 2015, those negotiations had stalled.

EPA proposes to revoke all food tolerances based on drinking water contamination, but it holds open the possibility that it might be able to allow some uses to continue. EPA takes no action to stop nonfood uses or to protect workers from unacceptable risks. Publication date was 11/06/2015.

January 2016

More than 80,000 people submit comments on the proposal, urging EPA to ban all uses of chlorpyrifos, not just on food crops, and to start proceedings to stop uses that harm workers. Some of the comments submitted during public comment periods on chlorpyrifos:

As a concerned American, I want the EPA to ban all uses of chlorpyrifos.

As a clinical psychologist, I have worked with many children who have experienced the negative repercussions of such toxins. These children have serious neurodevelopment impairments as a result of toxic exposure.

– Dr. T. S.,Novato, CA

A dear friend of mine's father had a beautiful garden. He had a pest problem. He hired a couple of men to come and take care of it using safe environmently friendly products. They used chlorpyrifos-based products.

After they left, he waited until the tomatoes ripened and ate one off the vine as was his fashion. He quickly developed horrible symptoms. Extensive memory loss. Partial blindness. And slurred speech. He then developed brain cancer.

He passed away almost 2 years ago now. He left behind a wife, 2 daughters and 4 grandchildren. He was only 54.

Chlorpyrifos kills. How many more families need to lose their grandparents, parents, children and grandchildren before you believe enough is enough?

– Heather,Russelville, AR

The EPA needs to act quickly on these neurotoxins when research suggests danger. It is especially outrageous that migrant farmworkers and their children, who have poor access to health and economic resources, should bear the primary risk that these pesticides bring.

– Anne,Vashon, WA

My last patient as a hospice volunteer was a migrant worker child dying of a brain tumor. It was wrenching. It was also enraging because, though unprovable, I knew it was due to exposure to toxic pesticides in the fields. This is unacceptable.

Please ban chlorpyrifos now and ban those that produce it from selling it overseas as was done with DDT. Thank you.

– Rebecca,Sedro Woolley, WA

My ex has Parkinson's Disease because he grew up near a farming community.

Food safety laws require EPA to revoke food residue tolerances after making the determination that there are no safe food uses of a pesticide. Because EPA’s November 2016 risk assessment found that there are no safe food uses of chlorpyrifos, tolerance revocation must necessarily follow. Therefore, the farmworker and health advocate groups withdrew their September 2016 Chlorpyrifos Suspension Petition as tolerance revocation would end most uses of chlorpyrifos that harm workers.

March 29, 2017

Two days before a court ordered deadline, the EPA refuses to ban chlorpyrifos, despite the overwhelming evidence that the pesticide harms children, workers and the environment.

April 5, 2017

Earthjustice—representing Pesticide Action Network and the Natural Resources Defense Council—asked the court to order the EPA to act based on the agency's own scientific conclusions, which, under the law, would require EPA to ban chlorpyrifos. Read the legal document.

A dozen health, labor and civil rights organizations, represented by Earthjustice filed an administrative appeal to the EPA, urging the federal government to ban chlorpyrifos. The attorney generals of New York, California, Washington, Massachusetts, Maine, Maryland and Vermont filed their own appeal calling for a ban also Monday. It is now up to EPA Administrator Scott Pruitt to decide the appeal.

June 27, 2017

The Associated Pressreveals that EPA Administrator Scott Pruitt met briefly with the chief executive of Dow Chemical—the largest producer of chlorpyrifos in the United States—before reversing EPA's push to ban the pesticide.

July 18, 2017

The 9th Circuit Court of Appeals declined to order EPA to make a new decision on banning chlorpyrifos, leaving the validity of the March EPA order to the administrative appeal and related lawsuit.

The EPA releases a series of documents in response to a FOIA request submitted by Earthjustice for communications between the agency and Dow, as well as certain trade associations. Dow Chemical is the largest producer of chlorpyrifos in the United States. Read the documents.

December 20, 2017

The court grants a motion to expedite the case and denied EPA’s motion to dismiss Earthjustice’s petition to review the Pruitt order on chlorpyrifos. Several states who have also called for a chlorpyrifos ban were granted permission to intervene in the case. Earthjustice’s opening brief is due on January 23.

Early January 2018

A National Marine Fisheries Service (NMFS) biological opinion finds that chlorpyrifos, malathion, and diazinon — all organophosphate pesticides — harm salmon and their habitat to the point that their survival and recovery are at risk. NMFS crafted the report to comply with a 2014 court deadline for the agency to determine whether these pesticides threatened to salmon with extinction. The biological opinion offers three options for protective measures including buffer zones, spray reduction technologies and pesticide stewardship programs. Read more about this case and the report.

July 9, 2018

Final arguments challenging EPA's refusal to ban chlorpyrifos took place in the 9th Circuit Court of Appeals in Seattle, Washington. It was the last hearing where health and labor groups represented by Earthjustice — as well as states — presented their arguments for a ban. A decision could happen in weeks or months.

August 9, 2018

The 9th Circuit Court of Appeals rules that EPA finalize its proposed ban on chlorpyrifos within 60 days, based on undisputed findings that the pesticide is unsafe for public health, and particularly harmful to children and farmworkers. “The Court ended EPA's shameful actions that have exposed children and farmworkers to this poison for decades,” said Earthjustice attorney Marisa Ordonia. “Finally, our fields, fruits, and vegetables will be chlorpyrifos-free.”